N-{4-[(E)-(4-Methyl­phen­yl)imino­meth­yl]phen­yl}acetamide

M Nawaz Tahir; Hazoor Ahmad Shad

doi:10.1107/S1600536811001887

. 2011 Jan 22;67(Pt 2):o443. doi: 10.1107/S1600536811001887

N-{4-[(E)-(4-Methylphenyl)iminomethyl]phenyl}acetamide

M Nawaz Tahir ^a,^*, Hazoor Ahmad Shad ^b

PMCID: PMC3051704 PMID: 21523107

Abstract

There are two symmetry-independent molecules in the asymmetric unit of the title compound, C₁₆H₁₆N₂O, that differ in conformation. The dihedral angles between the benzene rings in the two molecules are 44.35 (19) and 48.14 (17)°, but the rings twist in opposite directions. The acetamide groups make nearly equal dihedral angles of 25.4 (3) and 25.7 (3)° with the parent benzene rings. An S(6) ring motif is formed in each molecule by intramolecular C—H⋯O close contacts. In the crystal, strong N—H⋯O hydrogen bonds between acetamide groups generate a C(4) chain motif arranging the molecules into two symmetry-independent polymeric structures extending along [010].

Related literature

For related structures, see: Karlsen et al. (1988 ▶); Tahir et al. (2010 ▶). For graph-set notation, see: Bernstein et al. (1995 ▶).

Experimental

Crystal data

C₁₆H₁₆N₂O
M _r = 252.31
Triclinic,
a = 7.1044 (8) Å
b = 9.7393 (10) Å
c = 10.9236 (12) Å
α = 109.731 (5)°
β = 91.799 (6)°
γ = 100.679 (6)°
V = 695.51 (13) Å³
Z = 2
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 296 K
0.26 × 0.16 × 0.12 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T _min = 0.980, T _max = 0.990
10024 measured reflections
2453 independent reflections
1460 reflections with I > 2σ(I)
R _int = 0.059

Refinement

R[F ² > 2σ(F ²)] = 0.044
wR(F ²) = 0.112
S = 0.97
2453 reflections
339 parameters
3 restraints
H-atom parameters constrained
Δρ_max = 0.16 e Å⁻³
Δρ_min = −0.15 e Å⁻³

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: SAINT (Bruker, 2009 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶) and PLATON.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811001887/gk2340sup1.cif

e-67-0o443-sup1.cif^{(24.3KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811001887/gk2340Isup2.hkl

e-67-0o443-Isup2.hkl^{(118KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2A⋯O2ⁱ	0.86	2.00	2.854 (5)	172
N4—H4⋯O1ⁱⁱ	0.86	2.06	2.911 (4)	173
C13—H13⋯O1	0.93	2.40	2.922 (6)	116
C29—H29⋯O2	0.93	2.35	2.864 (6)	114

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Symmetry codes: (i) Inline graphic ; (ii) .

Acknowledgments

The authors acknowledge the provision of funds for the purchase of the diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan. The authors also acknowledge the technical support provided by Bana International, Karachi, Pakistan.

supplementary crystallographic information

Comment

The title compound (I, Fig. 1) is being reported as a part of our ongoing project related to the synthesis of various Schiff bases of 4-methylaniline. In this regard recently we have reported the synthesis and crystal structure of N-[(E)-1,3-benzodioxol-5-ylmethylidene]-4-methylaniline (Tahir et al., 2010).

The crystal structure of thiacetazone i.e., N-{4-[-(2-carbamothioylhydrazinylidene)methyl]phenyl}acetamide (Karlsen et al., 1988) has been published which contains the common moiety of N-(4-formylphenyl)acetamide as in (I).

The title compound consists of two molecules in the crystallographic asymmetric unit which differ from each other geometrically. In one molecule, the 4-methylaniline group A (C1—C7/N1), groups B (C8—C14) and C (N2/C15/C16/O1) of N-(4-formylphenyl)acetamide are planar with r. m. s deviation of 0.0062, 0.0169 and 0.0005 Å, respectively. The dihedral angle between A/B, A/C and B/C is 48.11 (15)°, 25.13 (25)° and 25.88 (27)°, respectively. In second molecule, the 4-methylaniline group D (C17—C23/N3), groups E (C24—C30) and F (N4/C31/C32/O2) of N-(4-formylphenyl)acetamide are planar with r. m. s deviation of 0.0292, 0.0146 and 0.0027 Å, respectively. The dihedral angle between D/E, D/F and E/F is 44.36 (17)°, 69.79 (17)° and 25.43 (23)°, respectively. In each molecule there exist S(6) ring motif (Bernstein et al., 1995) due to intramolecular H-bonding of C—H···O type (Table 1, Fig. 1). The molecules are stabilized in the form of one dimensional polymeric chains extending along the crystallographic b-axis due to intermolecular hydrogen bonds of N—H···O type (Table 1, Fig. 2). These C(4) chains (Bernstein et al., 1995) are formed via interaction of the amide groups. There does not exist any kind of strong π-interaction.

Experimental

Equimolar quantities of 4-methylaniline and N-(4-formylphenyl)acetamide were refluxed in methanol along with a few drops of acetic acid as catalyst for 30 min resulting in colorless solution. The solution was kept at room temperature. After six days colourless needles of the title compound were isolated.